Pressurized intraperitoneal aerosol chemotherapy (PIPAC): updated systematic review using the IDEAL framework

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in the Treatment of Gastric Cancer: Feasibility, Efficacy and Safety-A Systematic Review and Meta-Analysis

Background: Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an emerging technique for delivering chemotherapy directly to the peritoneum via a pressurized aerosol. Its growing attention stems from its effectiveness in treating peritoneal carcinomatosis (PC) originating from various primary tumors, with gastric cancer (GC) being among the most prevalent. This study aimed to systematically investigate PIPAC's therapeutic role in gastric cancer peritoneal metastasis (GCPM). Methods: The systematic review and meta-analysis followed the PRISMA 2020 guidelines, searching Pubmed, Web of Science, and SCOPUS databases. The meta-analysis of relative risks and mean differences compared patients undergoing one or two PIPAC sessions with those completing three or more, assessing various outcomes. Results: Eighteen studies underwent qualitative analysis, and four underwent quantitative analysis. Patients with three or more PIPAC procedures had shorter hospital stays (MD = -1.2; 95%CI (-1.9; -0.5); p < 0.001), higher rates of histopathological response (RR = 1.77, 95%CI 1.08; 2.90; p = 0.023), and significantly improved overall survival (MD = 6.0; 95%CI 4.2; 7.8; p < 0.001). Other outcomes showed no significant differences. Conclusions: PIPAC demonstrated efficacy in carefully selected patients, enhancing histopathologic response rates and overall survival without prolonging hospital stays. This study underscores the necessity for randomized controlled trials and precise selection criteria to refine PIPAC's implementation in clinical practice.

Review on treatment of pleural metastasis and malignant pleural effusion with Pressurized IntraThoracic Aerosol Chemotherapy (PITAC)

Background

Malignant pleural effusion (MPE) is a common and debilitating condition seen in advanced cancer disease, and life-expectancy is short. Symptoms include pain and severe shortness of breath. Current first-line treatment options include pleural drainage using catheters as well as pleurodesis. However, these treatment modalities are often inefficient and patients need repeated procedures. Pressurized IntraThoracic Aerosol Chemotherapy (PITAC) is a minimally invasive procedure, where antineoplastic agents are nebulized under pressure into the pleural space.

Content

We present the preliminary safety, feasibility, and response assessment data for PITAC based on a comprehensive literature review.

Summary

Five retrospective studies reported data on 38 PITACs in 21 patients. Data were heterogeneous and incomplete on several important aspects such as procedure, safety, local effect and long-term outcomes. PITAC seems technically feasible with a low risk of complications and may provide some reduction in MPE in selected cases.

Outlook

PITAC seems feasible, but prospective phase I and II studies are needed to define safety, indications, and efficacy.

Performance of different nebulizers in clinical use for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC)

OBJECTIVE

Technical ex-vivo comparison of commercial nebulizer nozzles used for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC).

METHODS

The performance of four different commercial nebulizer nozzles (Nebulizer; HurriChemTM; MCR-4 TOPOL®; QuattroJet) was analysed concerning: i) technical design and principle of operation, ii) operational pressure as function of the liquid flow rate, iii) droplet size distribution via laser diffraction spectrometry, iv) spray cone angle, spray cone form as well as horizontal drug deposition by image-metric analyses and v) chemical resistance via exposing to a cytostatic solution and chemical composition by means of spark optical emission spectral analysis.

RESULTS

The Nebulizer shows quasi an identical technical design and thus also a similar performance (e.g., mass median droplet size of 29 μm) as the original PIPAC nozzles (MIP/ CapnoPen). All other nozzles show more or less a performance deviation to the original PIPAC nozzles. The HurriChemTM has a similar design and principle of operation as the Nebulizer, but provides a finer aerosol (22 μm). The principle of operation of MCR-4 TOPOL® and QuattroJet differ significantly from that of the original PIPAC nozzle technology. The MCR-4 TOPOL® offers a hollow spray cone with significantly larger droplets (50 μm) than the original PIPAC nozzles. The QuattroJet generates an aerosol (22 μm) similar to that of the HurriChemTM but with improved spatial drug distribution.

CONCLUSION

The availability of new PIPAC nozzles is encouraging but can also have a negative impact if their performance and efficacy is unknown. It is recommended that PIPAC nozzles that deviate from the current standard should be subject to bioequivalence testing and implementation in accordance with the IDEAL-D framework prior to routine clinical use.

Second annual report from the ISSPP PIPAC database

Objectives

To monitor the results of PIPAC directed therapy based on data from the International Society for the Study of the Pleura and Peritoneum (ISSPP) PIPAC database.

Methods

Analysis of data from patients entered between June 15th, 2020, and February 28th, 2023.

Results

Twelve centers reported 2,456 PIPAC procedures in 809 patients (median 2, range 1-18) with peritoneal metastasis (PM) from different primary tumors. Approximately 90 % had systemic chemotherapy prior to PIPAC. Twenty-eight percent were treated in prospective protocols. Overall non-access rate was 3.5 %. Concomitant surgical procedures were performed during PIPAC in 1.6 % of the patients. Median length of stay was 2 days. A total of 95 surgical complications were recorded, but only 22 % of these were graded ≥3b. Seventeen-hundred-and-three adverse events were noted, and 8 % were classified ≥3. The rate of complete or major histological response (peritoneal regression grade score, PRGS≤2) increased between the first and the third PIPAC in the group of patients who were evaluated by PRGS, and a PRGS ≤2 or a reduction of the mean PRGS of at least 1 between first and third PIPAC were observed in 80 %. Disease progression (50 %) or technical issues (19 %) were the most important reasons for stopping PIPAC treatment. Median overall survival from first PIPAC directed treatment varied from 10.7 months (CI 8.7-12.5) in gastric cancer to 27.1 months (16.4-50.5) in mesothelioma.

Conclusions

The ISSPP PIPAC database provides substantial real-world data supporting the use of PIPAC directed therapy in patients with PM from different primary tumors.

Anatomical Targeting of Anticancer Drugs to Solid Tumors Using Specific Administration Routes: Review

Despite remarkable recent progress in developing anti-cancer agents, outcomes of patients with solid tumors remain unsatisfactory. In general, anti-cancer drugs are systemically administered through peripheral veins and delivered throughout the body. The major problem with systemic chemotherapy is insufficient uptake of intravenous (IV) drugs by targeted tumor tissue. Although dose escalation and treatment intensification have been attempted in order to increase regional concentrations of anti-tumor drugs, these approaches have produced only marginal benefits in terms of patient outcomes, while often damaging healthy organs. To overcome this problem, local administration of anti-cancer agents can yield markedly higher drug concentrations in tumor tissue with less systemic toxicity. This strategy is most commonly used for liver and brain tumors, as well as pleural or peritoneal malignancies. Although the concept is theoretically reasonable, survival benefits are still limited. This review summarizes clinical results and problems and discusses future directions of regional cancer therapy with local administration of chemotherapeutants.

Response Evaluation in Patients with Peritoneal Metastasis Treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC)

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) directed therapy emerged as a treatment of peritoneal metastasis (PM) a decade ago. The response assessment of PIPAC is not uniform. This narrative review describes non-invasive and invasive methods for response evaluation of PIPAC and summarizes their current status. PubMed and clinicaltrials.gov were searched for eligible publications, and data were reported on an intention-to-treat basis. The peritoneal regression grading score (PRGS) showed a response in 18-58% of patients after two PIPACs. Five studies showed a cytological response in ascites or peritoneal lavage fluid in 6-15% of the patients. The proportion of patients with malignant cytology decreased between the first and third PIPAC. A computed tomography showed stable or regressive disease following PIPAC in 15-78% of patients. The peritoneal cancer index was mainly used as a demographic variable, but prospective studies reported a response to treatment in 57-72% of patients. The role of serum biomarkers of cancer or inflammation in the selection of candidates for and responders to PIPAC is not fully evaluated. In conclusion, response evaluation after PIPAC in patients with PM remains difficult, but PRGS seems to be the most promising response evaluation modality.